Short message service (SMS) enables mobile subscribers to easily send and receive text messages via wireless handsets. Although specifications and industry standards related to SMS are constantly evolving and being modified, SMS messages have traditionally been used to convey readable text information, where the text can include any combination of characters that can be entered via a keypad or keyboard. Multimedia message service (MMS) extends the basic SMS concept to include a variety of message content types, including text, still images, video, and audio.
SMS delivery service provides a mechanism for transmitting messages to and from SMS capable terminals (e.g., wireless handsets, personal computers, etc.) via the signaling component of the wireless communications network. With particular regard to the sending and receiving of SMS messages by a wireless handset, a signaling network provides the transport facilities necessary to communicate short messages between a store-and-forward network element, known as a short message service center (SMSC), and a wireless handset. In contrast to earlier text message transmission services, such as alphanumeric paging, SMS technology is designed to provide guaranteed delivery of an SMS message to a destination. That is, if a temporary network failure, or the unavailability of a message recipient prohibits the immediate delivery of an SMS message, then the SMS message is stored in the network (i.e., at an SMSC) until the destination/intended message recipient becomes available.
SMS is a messaging feature of Interim Standard 41 (IS-41) and Global System for Mobile Communication (GSM) networks. In IS-41 and GSM mobile network environments, SMS service makes use of mobile application part (MAP), which defines the methods and mechanisms for mobility management signaling communications in a wireless network. The American MAP standard is published by Telecommunication Industry Association and is referred to as IS-41 MAP, while the international standard is defined by the European Telecommunications Standards Institute and is referred to as GSM MAP. Depending upon the particular implementation, SMS service may also utilize the signaling connection control part (SCCP) and transaction capabilities application part (TCAP) components of the SS7 protocol. Within the context of SS7 signaling over Internet protocol (IP), an IP adaptation protocol such as the SCCP user adaptation (SUA) layer defined by the Internet Engineering Task Force (IETF) may also be utilized to facilitate SMS and MMS service. Other signaling protocols, such as session initiation protocol (SIP) may also be used to transport messaging service content (e.g., SMS, MMS, instant message (IM)) through a communications network.
The SCCP, TCAP, and MAP layers of a signaling message may include called and calling party information components. Among the called and calling party information included in these components are called and calling party address parameters. In general, the purpose of these parameters is to identify the called and calling subscribers. Typically, these parameters are in the form of an international mobile station identification (IMSI), mobile identification number (MIN), mobile directory number (MDN), and mobile station international ISDN number (MSISDN). Wireline telephone number identifiers, or electronic mail address identifiers may also be utilized.
Wireless network elements involved in SMS communication include a mobile station (MS), mobile switching center (MSC), visitor location register (VLR), home location register (HLR), and short message service center (SMSC). The MS can either originate or terminate SMS messages. When a MS originates an SMS message to another destination, it is typically called mobile originated SMS (MS-SMS) message. A mobile terminated SMS (MT-SMS) refers to a case where an SMS message is terminated at a MS.
In an effort to protect public safety and national security, Congress passed Public Law 103-414, the Communications Assistance for Law Enforcement Act (CALEA), which sets forth the interception assistance capability requirements that telecommunications carriers need to meet and maintain within their networks to assist law enforcement in conducting electronic surveillance. These requirements apply to the intercept of wireline and wireless communications, including SMS and MMS communications
Accordingly, there exists a long-felt need for methods, systems, and computer program products for surveillance of messaging service messages in a communications network. However, neither the CALEA statute nor the SMS or MMS specifications specify methods for surveillance of messaging service communications. Surveillance of messaging service messages may be difficult because, unlike calls, store-and-forward type messaging service communications may be temporarily buffered and delivered long after they are originally sent.